macho: port arm64 and x86_64 compact unwind defs verbatim
We do not need more for the purpose of parsing and synthesising
unwind info by the linker. If we ever decide to generate unwind
info for Zig by the compiler, we can re-add packed struct defs
again.
c70a3d9022Jakub Konka committed on 1/19/2023, 2:44:42 AMparent35f5d43